System and methods for monitoring physical therapy and rehabilitation of joints

ABSTRACT

A system for monitoring a joint of a patient includes multiple sensors to be disposed near a joint and to measure or observe actions or physical quantities associated with the joint; and at least one communications module coupled to the sensors to receive data from the sensors and to transmit sensor information to an external device. In some embodiments, the sensors are implantable near the joint. In other embodiments, the sensors are disposed in a sensor module that is positioned adjacent the skin of the patient near the joint.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a continuation of U.S. patent application Ser. No.15/077,809, filed Mar. 22, 2016, which claims the benefit of both U.S.Provisional Patent Application Ser. No. 62/136,892, filed Mar. 23, 2015,and U.S. Provisional Patent Application Ser. No. 62/136,925, filed Mar.23, 2015, all of which are incorporated herein by reference in theirentirety.

FIELD

The present invention is directed to the area of orthopedic implants andrehabilitation. The present invention is also directed to systems andmethods for monitoring an orthopedic implant and rehabilitation afterorthopedic replacement surgery.

BACKGROUND

Joint replacement surgery is a common orthopedic procedure for jointssuch as the shoulder, hip, knee, ankle, and wrist. In situations wherethe patient has worn-out or damaged a joint, it is possible to replacethe joint with an implant that can merge with the skeletal structure andrestore pain free movement and function. Prior to implanting prostheticcomponents in a joint of a patient, a surgeon generally resects at leasta portion of the patient's native bone in order to create a platform,recess, or cavity for receiving at least a portion of the prostheticcomponents being implanted. During the process of implanting theprosthetic components muscles and tendons must be repositioned andreattached.

The patient must go through physical therapy in order to recover fromthis major surgery. The patient must exercise regularly as well as pushfor flexibility and balance in muscles that have been displaced. Whilethe goal is to have the patient extend their range of motion, there canbe an increased risk of falls or over-extension that can damage theimplant and injure the patient. If the patient does not push theirrehabilitation and achieve the needed range of motion, they will findthemselves with a stiff joint which may require an additional surgicaloperation (MUA—Manipulation Under Anesthesia) to achieve an adequaterange of motion to maintain their active lifestyle. Measuring ormonitoring the progress of the physical therapy can be problematic butis very useful for maintaining the patient's dedication andparticipation.

BRIEF SUMMARY

One embodiment is a system for monitoring a joint of a patient thatincludes multiple sensors to be disposed near a joint and to measure orobserve actions or physical quantities associated with the joint; and atleast one communications module coupled to the sensors to receive datafrom the sensors and to transmit sensor information to an externaldevice.

In at least some embodiments, the at least one communication unitincludes a sensor processor to receive the sensor data and a wirelesscommunications unit to wirelessly transmit the sensor information to orthrough the external device. In at least some embodiments, at least oneof the sensors is configured and arranged to be implanted in thepatient.

In at least some embodiments, the system further includes a sensormodule having a housing, the sensors disposed in the housing, and the atleast one communication unit disposed in the housing, where the sensormodule is configured and arranged to be disposed adjacent skin of thepatient to monitor the joint. In at least some embodiments, the sensormodule further includes an adhesive pad coupleable to the housing toadhesively adhere the sensor module to the skin of the patient for atleast one hour. In at least some embodiments, the system furtherincludes a wearable article to receive the sensor module within thewearable article and to be worn by the patient so that the sensor moduleis disposed near the joint.

In at least some embodiments, the sensors include at least one sensor toprovide sensor data that can be processed to determine a range of motionof the joint. In at least some embodiments, the at least one sensorincludes a first accelerometer in combination with at least one of asecond accelerometer, a gyroscope, or a magnetometer. In at least someembodiments, the sensors include at least two proximity sensors toprovide sensor data that can be processed to determine a number ofrepetitions of joint movement. In at least some embodiments, the sensorsinclude at least one temperature sensor or pulse sensor.

In at least some embodiments, the system further includes a patientdevice to receive the sensor information from the at least onecommunications module and to process the sensor information and displaythe processed information for viewing by the patient. In at least someembodiments, the system further includes a clinician device to receivethe sensor information from the at least one communications module orfrom a patient device and to process the sensor information and displaythe processed information for viewing by a clinician.

Another embodiment is a sensor module that includes a housing to bedisposed near a joint of a patient and adjacent to skin of the patient;multiple sensors disposed within the housing; a sensor processordisposed within the housing and coupled to the plurality of sensors toreceive sensor data from the plurality of sensors; and a communicationsunit disposed within the housing and coupled to the sensor processor totransmit sensor information, based on the sensor data, to an externaldevice. The sensors include at least one sensor to provide sensor datathat can be processed to determine a range of motion of the joint;

In at least some embodiments, the sensor module further includes anadhesive pad coupleable to the housing to adhesively adhere the sensormodule to the skin of the patient for at least one hour. In at leastsome embodiments, the adhesive pad includes at least one first locatingfeature and the housing includes at least one second locating featurehaving a shape complementary to a shape of the at least one firstlocating feature to facilitate alignment of the adhesive pad with thehousing. In at least some embodiments, one of the at least one firstlocating feature or the at least one second locating feature includes amagnet and another one of the at least one locating feature or the atleast one second locating feature includes a second magnet or amagnetically attractive material to facilitate coupling of the adhesivepad to the housing.

In at least some embodiments, the sensor module further includes awearable article to receive the housing of the sensor module within thewearable article and to be worn by the patient so that the housing ofthe sensor module is disposed near the joint.

In at least some embodiments, the sensors include a first accelerometerin combination with at least one of a second accelerometer, a gyroscope,or a magnetometer. In at least some embodiments, the sensors include atleast two proximity sensors configured and arranged to provide sensordata that can be processed to determine a number of repetitions of jointmovement. In at least some embodiments, the sensors include at least onetemperature sensor or pulse sensor.

A further embodiment is a system for monitoring rehabilitation. Thesystem includes multiple sensors to be disposed near a rehabilitationsite on a patient to measure or observe actions or physical quantitiesassociated with the rehabilitation; and at least one communicationsmodule coupled to the sensors to receive data from the sensors and totransmit sensor information to an external device.

Yet another embodiment is a sensor module including a housing to bedisposed near a rehabilitation site of a patient and adjacent to skin ofthe patient; multiple sensors disposed within the housing; a sensorprocessor disposed within the housing and coupled to the sensors toreceive sensor data from the sensors; and a communications unit disposedwithin the housing and coupled to the sensor processor to transmitsensor information, based on the sensor data, to an external device. Thesensors include at least one sensor configured and arranged to providesensor data that can be processed to determine a range of motion at therehabilitation site.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting and non-exhaustive embodiments of the present invention aredescribed with reference to the following drawings. In the drawings,like reference numerals refer to like parts throughout the variousfigures unless otherwise specified.

For a better understanding of the present invention, reference will bemade to the following Detailed Description, which is to be read inassociation with the accompanying drawings, wherein:

FIG. 1 is a schematic diagram of one embodiment of a system formonitoring rehabilitation of a patient after implant surgery, accordingto the invention;

FIG. 2 is a schematic diagram of one embodiment of a computing devicefor use in the system of FIG. 1, according to the invention;

FIG. 3 is a schematic diagram of one embodiment of components of thesystem of FIG. 1 implanted near a knee replacement implant, according tothe invention;

FIG. 4 is a schematic diagram of another embodiment of components of thesystem of FIG. 1 implanted near a knee replacement implant, according tothe invention;

FIG. 5 is a schematic diagram of one embodiment of components of thesystem of FIG. 1 implanted near a finger joint replacement implant,according to the invention;

FIG. 6 is a schematic diagram of one embodiment of a sensor module thatcontains sensors for monitoring rehabilitation of a patient afterimplant surgery, according to the invention;

FIG. 7A is a top view of a second embodiment of a sensor module thatcontains sensors for monitoring rehabilitation of a patient afterimplant surgery, according to the invention;

FIG. 7B is a bottom view of the sensor module of FIG. 7A, according tothe invention;

FIG. 8A is a top view of a third embodiment of a sensor module thatcontains sensors for monitoring rehabilitation of a patient afterimplant surgery, according to the invention;

FIG. 8B is a top view of the sensor module of FIG. 8A with an adhesivepad, according to the invention;

FIG. 9A is a top view of a fourth embodiment of a sensor module thatcontains sensors for monitoring rehabilitation of a patient afterimplant surgery, according to the invention;

FIG. 9B is a top view of the sensor module of FIG. 8A without theadhesive pad, according to the invention;

FIG. 9C is a top view of one embodiment of an adhesive pad for thesensor module of FIG. 8A, according to the invention;

FIG. 9D is a bottom view of one embodiment of the sensor module of FIG.9A for use with the adhesive pad of FIG. 9C, according to the invention;

FIG. 10 is a diagram of one embodiment of a user interface for a mobiledevice to display information obtained from a sensor module, accordingto the invention;

FIG. 11 is a diagram of another embodiment of a user interface todisplay information obtained from a sensor module, according to theinvention; and

FIG. 12 is a diagram of a third embodiment of a user interface for amobile device to display information obtained from a sensor module,according to the invention.

DETAILED DESCRIPTION

The present invention is directed to the area of orthopedic implants andrehabilitation. The present invention is also directed to systems andmethods for monitoring an orthopedic implant and rehabilitation afterorthopedic replacement surgery.

A system, as described herein, can be used to monitor the healingprocess of the patient as well as monitor or verify the extent of thepatient's activity. The system includes one or more sensors that cancommunicate with a processor that can produce information, based on thesensor readings and data, that can facilitate the patient or anotheruser, such as a clinician, doctor, or physical therapist, monitoring thepatient's activity, the status of the orthopedic implant or surroundingtissues, or the effects of rehabilitation or other therapy. It will beunderstood, however, that the systems, devices, and methods describedherein can be used in the context of other surgeries or evenrehabilitation without surgical intervention. The sensors, describedbelow, are placed near a rehabilitation site, such as a surgical site orthe body portion to be rehabilitated.

The system may also provide alerts if patient tissue becomes inflamed orif the effectiveness of, or compliance to, rehabilitation therapy isinsufficient. In at least some embodiments, at least one sensor isimplanted and, in some embodiments, all of the sensors may be implanted.In at least some embodiments, at least one sensor is external to thepatient and, in some embodiments, all of the sensors are external. Forexample, one or more sensors may be provided on a device that is appliedto the skin of the patient or is carried in a brace or other article(for example, socks, shirt, shorts, pants, glove, or the like) that isworn by the patient.

In at least some embodiments, the one or more sensors communicate with asensor processor on the device containing or near the sensors. In atleast some embodiments, the sensor processor, or, alternatively oradditionally, the sensors, communicate with a processor of a patientdevice, such as a mobile phone, tablet, computer or the like, or with aprocessor of a clinician device, such as a mobile phone, tablet,computer or the like.

FIG. 1 illustrates one embodiment of a system 100 for monitoring anorthopedic implant and rehabilitation after orthopedic replacementsurgery. The system 100 includes one or more sensors 102, an optionalsensor processor 104, a patient device 106, a clinician device 108, anda network 110. In other embodiments, the system may include fewer ormore components, but the system typically includes the sensor(s) 102 anda processor (such as sensor processor 104, patient device 106, orclinician device 108) to communicate with the sensor(s) and provideinformation based on the sensor data. In at least some embodiments, theone or more sensors 102 may be combined into a sensor module that mayalso include the sensor processor 104.

In at least some embodiments, the one or more sensors 102 and theoptional sensor processor 104 can be implanted into the patient. Inother embodiments, the one or more sensors and the optional sensorprocessor 104 can be provided in a device that is external to thepatient such as, for example, a device that is applied to the skin ofthe patient or is carried in a brace or other article or textile that isworn by the patient. In yet other embodiments, at least one of thesensors (or all of the sensors) are implanted and the optional sensorprocessor and, optionally, one or more sensors external to the patient.

In FIG. 1, the solid lines indicate communication between components inat least some embodiments of the system. Dotted lines indicatealternative or additional modes of communication between components. Inaddition to the communication illustrated in FIG. 1, in at least someembodiments, the sensor processor 104 or sensors 102 may alsocommunicate directly with the clinician device. Communications caninclude, but is not limited to, wireless communication, wiredcommunication, optical communication, ultrasonic communication, or thecombination thereof. Satellite communication, cellular communication,Bluetooth, near field communications (NFC), Infrared Data Associationstandard (IrDA), wireless fidelity (WiFi), and worldwideinteroperability for microwave access (WiMAX) are non-limiting examplesof wireless communication that can be used for communications. Ethernet,digital subscriber line (DSL), fiber to the home (FTTH), and plain oldtelephone service (POTS) are non-limiting examples of wiredcommunication that can be used for communications.

The network 110 can be any suitable type of network including, but notlimited to, a personal area network (PAN), local area network (LAN),metropolitan area network (MAN), wide area network (WAN), the Internet,or any combination thereof. In at least some embodiments, the network110 can be bypassed to provide direct connection between components. Itwill be understood that other devices, such as a server or server farm,memory storage device, or the like can be connected to the patientdevice 106 or clinician device 108 through the network 110 or directly.For example, a server may be coupled to the patient device 106 orclinician device 108 that stores patient or other medical information,applications, user interfaces, a web interface, or the like for accessby the patient device 106 or clinician device 108.

The patient device 106 and the clinician device 108 can be any of avariety of devices, such as computers (for example, a notebook computer,a mobile medical station or computer, a server, a mainframe computer, ora desktop computer), mobile devices (for example, a cellular phone orsmartphone, personal digital assistant, or a tablet), or any othersuitable device. In at least some embodiments, the clinician device 108can be incorporated into a medical station or system.

FIG. 2 illustrates one embodiment of a computing device 201 for use asthe patient device 106 or clinician device 108. The computing device 201includes a processor 212 and a memory 214, a display 216, and an inputdevice 218. The computing device 201 can be local to the user or caninclude components that are non-local to the computer including one orboth of the processor 212 or memory 214 (or portions thereof). Forexample, in some embodiments, the user may operate a terminal that isconnected to a non-local processor or memory.

The computing device 201 can utilize any suitable processor 212including one or more hardware processors that may be local to the useror non-local to the user or other components of the computing device.The processor 212 is configured to execute instructions provided to theprocessor. Such instructions can include any of the steps of methods orprocesses described herein.

Any suitable memory 214 can be used for the computing device 212. Thememory 214 illustrates a type of computer-readable media, namelycomputer-readable storage media. Computer-readable storage media mayinclude, but is not limited to, nonvolatile, non-transitory, removable,and non-removable media implemented in any method or technology forstorage of information, such as computer readable instructions, datastructures, program modules, or other data. Examples ofcomputer-readable storage media include RAM, ROM, EEPROM, flash memory,or other memory technology, CD-ROM, digital versatile disks (“DVD”) orother optical storage, magnetic cassettes, magnetic tape, magnetic diskstorage or other magnetic storage devices, or any other medium which canbe used to store the desired information and which can be accessed by acomputing device.

Communication methods provide another type of computer readable media;namely communication media. Communication media typically embodiescomputer-readable instructions, data structures, program modules, orother data in a modulated data signal such as a carrier wave, datasignal, or other transport mechanism and include any informationdelivery media. The terms “modulated data signal,” and “carrier-wavesignal” includes a signal that has one or more of its characteristicsset or changed in such a manner as to encode information, instructions,data, and the like, in the signal. By way of example, communicationmedia includes wired media such as twisted pair, coaxial cable, fiberoptics, wave guides, and other wired media and wireless media such asacoustic, RF, infrared, Bluetooth, near field communication, and otherwireless media.

The display 216 can be any suitable display device, such as a monitor,screen, display, or the like, and can include a printer. The inputdevice 218 can be, for example, a keyboard, mouse, touch screen, trackball, joystick, voice recognition system, camera, microphone, or anycombination thereof, or the like.

Returning to FIG. 1, the sensor processor 104 can be any suitableprocessor including one or more hardware processors. The sensorprocessor 104 is configured to execute instructions provided to theprocessor. The sensor processor 104 is configured to receive sensor datafrom the sensor(s) and communicate with the patient device 106, network110, clinician device 108, or any combination thereof. Optionally, thesensor processor 104 may also process or analyze the sensor data and mayhave instructions stored thereon to perform such processing or analysisincluding, for example, instructions to perform the steps of any of theprocessing or analysis described herein. In at least some embodiments,one or more of the sensor(s) 102 can each include a processor thatperhaps some or all of the functions of the sensor processor 104.

The one or more sensors 102 are provided to monitor the orthopedicimplant and surrounding tissue or monitor rehabilitation afterorthopedic surgery whether an implant was required or not, or to providepreparatory therapy in advance of a surgery, or any combination thereof.This disclosure will use an orthopedic knee implant as an example, butit will be understood that other joint implants, such as, for example,implants for the shoulder, hip, ankle, wrist, or any other joint, or anyother orthopedic device, such as an orthopedic spinal implant, whetherjoint replacement, joint resurfacing, soft tissue reconstruction,debridement, limb correction surgery, ligament replacement, or the like.

Any suitable type of sensor 102 can be used including, but not limitedto, accelerometers, magnetometers, gyroscopes, proximity sensors,infrared sensors, ultrasound sensors, thermistors or other temperaturesensors, cameras, piezoelectric or other pressure sensors, sonarsensors, external fluid sensor, skin discoloration sensor, pH sensor,microphone, or the like or any combination thereof. In at least someembodiments, the system 100 includes at least one, two, three, four,five, six, or more different types of sensors 102. The system mayinclude at least one, two, three, four, five, six, eight, ten, or moresensors 102.

The one or more sensors 102 can be used to measure, monitor, orotherwise observe one or more aspects of the orthopedic device,surrounding tissue, or patient activity, or the like. The following areexamples of observations or measurements that can be made or interpretedusing one or more of the sensors: number of steps, repetitions of anexercise, repetitions of joint movement (e.g., joint pivoting), type ofexercise being performed, or other actions; stability, or lack thereof;flexion angle or range of motion; rate of motion; temperature of skin orinternal tissues; pulse or pulse profile or heart rate recovery timeafter activity; particles in a joint space; ultrasound images, flowmeasurements, or Doppler measurements; sonar images, flow measurements,or Doppler measurements; pressure or load bearing measurements;detection of a limp or body orientation (e.g., subluxation, posture,scoliosis) or a change in body orientation; joint shock or impactmonitoring; sleep profile or rest duration; gait analysis,body/limb/joint alignments; or the like. A system 100 can observe ormeasure one or more of these items or any combination of the items.

The following provides further details on some of these measurements orobservations. One or more sensors (for example, accelerometers,gyroscopes, magnetometers, proximity sensors, or the like) may countsteps or repetitions of an exercise or number of joint movements orother actions experienced by the sensor, and may be utilized todetermine what type of exercise or movement is occurring. This can beused, for example, to monitor patient activity, monitor compliance withexercise therapy, or monitor possible signs of pain or other conditionsthat may hinder or aid rehabilitation. The sensor data may also be usedto monitor changes in activity or trends in activity.

One or more sensors (for example, accelerometers, gyroscopes,magnetometers, proximity sensors, or the like) may sense or detect orcompute the range of motion of the sensor, joint, or other portion ofthe patient body or the flexion of the joint. This can be used, forexample, to monitor patient rehabilitation, patient activity, monitorcompliance with exercise therapy, or monitor possible signs of pain orother conditions that may hinder or aid rehabilitation. These sensors orother sensors may be used to monitor shock to, or impact on, theorthopedic device or tissue around the orthopedic device. The sensordata may also be used to monitor changes in range of motion or flexionor trends in range of motion or flexion.

As an illustrative example, two proximity sensors (for example, amagnetometer and a magnet—such as a permanent magnet, electromagnet, orpolymagnet or the like) can be implanted or placed externally onopposing sides of a joint. The distance between the two proximitysensors can be detected, measured, or otherwise observed. The distancebetween the two proximity sensors can be correlated to flexion or rangeof motion of the patient's joint. The variation in the distance betweenthe two proximity sensors can be used to measure number of repetitionsof joint motion or to monitor compliance with patient therapy. Thevariation in distance among repetitions or the trend in the variationamong repetitions may be used to monitor improvement in jointflexibility or may indicate pain or other deleterious physicalconditions of orthopedic implant or surrounding tissue. This informationcan be used to measure progress in the physical therapy following thesurgery.

As another illustrative example, one or more accelerometers can measurethe acceleration from joint movement. A ratio of measured accelerationbetween accelerometers of known distance apart can be used to assess thejoint movement and region of motion or flexion by calculating the centerof rotation about which the device is being rotated. This informationcan be used for the same purposes as described in the preceding example.

In another illustrative example, 1) an accelerometer and 2) a gyroscopeor magnetometer (which indicates direction relative to magnetic north)can be used to measure range of motion, rate of motion, number ofrepetitions, or the like. This information can be used for the samepurposes as described in the preceding two examples.

In another illustrative example, a single sensor such as anaccelerometer, gyroscope, or magnetometer can be used to measure orotherwise observe range of motion, rate of motion, number ofrepetitions, or the like. In at least some embodiments, thesemeasurements or other observations are determined using the sensor dataand one or more assumptions about the sensor or sensor data based on,for example, the recognition of patterns in the sensor data, the upperand lower limits of the range in the data collected, or the like. Suchinformation can be used in a manner similar to that in the precedingthree examples.

One or more sensors (for example, thermistors or infrared sensors) maysense or detect or compute a temperature or a change in temperature or atemperature trend. The temperature may be a skin temperature or internaltemperature of, for example, tissue near the orthopedic device. Thetemperature measurements may be used, for example, to indicate thepossibility of inflammation or pain or another condition that may hinderrehabilitation or patient health. The temperature measurement may alsobe used, for example, to monitor if icing is being performedeffectively, which can help reduce inflammation and aid healing. Thesesensors may also or alternatively be used to sense, detect, or measure apulse, a change in pulse, trends in the patient's pulse, a pulseprofile, or heart rate recovery after patient activity (such as exerciseor other exertion). In addition, when a joint is immobilized by a cast,monitoring temperature and pulse can facilitate monitoring of thepatient's health and possibility of inflammation or other deleteriouscondition.

One or more sensors (for example, ultrasound or sonar sensors or camerasor the like) can sense or detect or compute particles or density ofparticles or a particle density trend. These sensors may also be used tosense the tissue surrounding the orthopedic device, detect wear ordimensional changes on the orthopedic device or surrounding tissue, orthe like. Ultrasound and sonar sensors may also be used to determine howclose other parts of the knee (or other joint) are to the implant.

One or more sensors (for example, piezoelectric, strain gage, or otherpressure or load bearing sensors) can sense or detect or computepressure or load with or around the sensor or orthopedic device. Thesensor data may also be used to monitor changes in range of pressure orload bearing or trends in pressure or load bearing. These sensors orother sensors may be used to monitor shock to, or impact on, theorthopedic device or tissue around the orthopedic device. A pressure orload bearing sensor may also be used to detect swelling of the tissuearound the orthopedic implant. Multiple pressure or load bearing sensorsmay also be used to detect flexion (which may be indicated by a uniaxialstretching of the tissue) and swelling (which may be indicated bybiaxial stretching of the tissue.)

Power can be provided to the sensors 102 and optional sensor processor104 using any suitable power source including, but not limited to,primary cells, rechargeable batteries, storage capacitors, other powerstorage devices, or the like or any combination thereof. In someembodiments, the power can be provided by a kinetic energy power sourcethat utilizes the movements of the patient's body to generate power forthe components or to or to charge a battery or storage capacitor orother power storage device coupled to the components. In someembodiments, power can be provided by an induction power source disposedon or adjacent the patient's body (such as, for example, disposed in abrace or other article of clothing worn by the patient or in a mat uponwhich the patient sits or sleeps) and radiates electromagnetic energy tothe sensors or optional sensor processor to power these components or tocharge a battery or storage capacitor or other power storage devicecoupled to the components. Other wireless power sources can be used inplace of the induction power source such as, for example, a wirelesspower source that utilizes ultrasound or WiFi or other rf power signalsto generate power in the for charging a battery or storage capacitor orother power storage device.

In addition, for sensors or optional sensor processor disposed outsidethe body, a charging port can be provided for charging the battery orstorage capacitor or other power storage device from a source such as awall socket. It will be understood that in some embodiments there may bemultiple methods for providing power to the component or to a powerstorage device associated with the component. All of the sensors andoptional sensor processor may be coupled to the same power source orsome of the sensors (or even all of the sensors) and sensor processormay have individual power sources.

In at least some embodiments, the sensors and optional sensor processorcan be active at all times to measure, monitor, or otherwise observe. Inother embodiments, one or more of the sensors and optional sensorprocessor can be active periodically (with a period of, for example, 15or 30 seconds or 1, 5, 10, 15, or 30 minutes or 1, 2, 3, 4, 6, 12, or 24hours) or randomly to measure, monitor, or otherwise observe.Optionally, the period may be programmable. In addition, the period maybe optionally altered based on data from one or more of the sensors. Inyet other embodiments, one or more of the sensors and optional sensorprocessor may be activated manually or automatically by the sensormodule, patient device, clinician device, or other device. In at leastsome embodiments, the sensors and optional sensor processor may havedifferent activation schedules (continuous, periodic, random, ormanual). For example, a sensor to measure temperature may do soperiodically, a sensor to measure number of steps or movement of thejoint may be continuous, and a sensor to measure range of motion may beactivated manually by the sensor module, patient device, or cliniciandevice when the patient performs rehabilitation exercises.

FIG. 3 illustrates a knee joint 350 having an orthopedic knee implant352 and sensors 302 a, 302 b, 302 c, 302 d implanted around the kneejoint 350. The orthopedic knee implant 352 can be made of, for example,surgical steel, carbon fiber, Kevlar fiber, or a combination thereof. Tomonitor the recovery of the joint 350, the set of sensors can, forexample, include a first proximity sensor 302 a, a second proximitysensor 302 b, a thermal and acoustic sensor 302 c, and a shock sensor302 d. It will be understood that other or different sensors can beused. The thermal and acoustic sensor 302 c can be directly coupled to aportion of the orthopedic knee implant 352 or disposed in the tissueaway from the device. The thermal and acoustic sensor 302 c can detectany unexpected contact between the component parts of the orthopedicknee implant 352. Any acoustic noise or vibrations that come from theorthopedic knee implant 352 can be sampled and recorded by the thermaland acoustic sensor 302 c. The thermal and acoustic sensor 302 c mayalso be used to measure temperature of the implant 352 or surroundingtissue.

The shock sensor 302 d can record or measure shocks or impacts to theimplant 352. In at least some embodiments, the shock sensor 302 d can bebiased to only record shock or impact events over a preset threshold.

In at least some embodiments, the first proximity sensor 302 a and thesecond proximity sensor 302 b can be mounted along a centerline 212 ofthe joint to work in tandem. The distance between the first proximitysensor 302 a and the second proximity sensor 302 b can be detected andrecorded. The distance between the first proximity sensor 302 a and thesecond proximity sensor 302 b can be correlated to the deflection of theorthopedic knee implant 352. This information can be used, for example,to measure progress in the physical therapy following the surgery toinstall the orthopedic knee implant 352. Other arrangements of sensorscan be used to measure range of motion, as described herein. Theproximity sensor 302 a, 302 b may also be used to observe or determine,for example, number of steps, number of joint movements, or exerciserepetitions.

The sensors 302 a, 302 b, 302 c, 302 d communicate with the sensorprocessor 104), patient device 106, or clinician device 108 of FIG. 1.The sensor processor may be implanted with the body of the patient ormay be disposed outside the body. For example, the patient can wear aknee brace that includes sensor processor and an optional inductionpower source used to power one or more of the sensors.

It will be recognized that other arrangements of sensors can beimplanted during the surgery for placement of the orthopedic kneeimplant 352. FIG. 4 illustrates another knee joint 450 having anorthopedic knee implant 452 and sensors 402 a, 402 b implanted aroundthe knee joint 450. The sensors 402 a, 402 b can be implanted in thetissue surrounding the knee joint, in the bone of the knee, or in theimplant 452. If the orthopedic knee implant 452 is flexed in thedirection of a deflection angle 454, by bending the knee, the separationdistance 456 will be decreased until the flexing is reversed. The firstproximity sensor 402 a and the second proximity sensor 402 b measure orotherwise observe the separation distance 456 which can then be used todetermine the deflection angle 454. In at least some embodiments, thecycling of the deflection angle 454 can also be used as a step counter.It will be understood that other or different sensors can be usedinstead of, or in addition to, proximity sensors 402 a, 402 b.

Similar techniques and arrangements can be used with other jointsincluding, but not limited to, the finger joint, wrist joint, elbowjoint, shoulder joint, hip joint, ankle joint, or toe joint. FIG. 5illustrates one example of an arrangement disposed around a finger joint550 with a finger joint implant 552, proximity sensors 502 a, 502 b,temperature sensor 502 c, and pulse sensor 502 d. The proximity sensors502 a, 502 b can provide information similar to the embodimentsdescribed with respect to FIGS. 3 and 4. The temperature sensor 502 ccan be used to measure temperature of the implant 552 or surroundingtissue and the pulse sensor 502 d can be used to measure the patient'spulse.

FIG. 6 illustrates one embodiment of an implantable sensor module 658with one or more sensors 602 a, 602 b, a housing 660, a power source662, a circuit carrier 664, a storage and communications unit 666, and atreatment unit 668. The one or more sensors can be any of the sensorsdescribed above including, for example, a proximity sensor and anacoustic sensor. Other embodiments of a sensor module can include moreor fewer components.

The housing 660, can be formed of materials that are resistant toingress of body fluids including metals, polymers, or the like such as,for example, polycarbonate, stainless steel, Kevlar fibers, or the like.The one or more sensors 602 a, 602 b can be mounted on a circuit carrier664 (for example, a printed circuit board, a printed flex circuit, asemiconductor substrate, a glass substrate, or a printed Mylarsubstrate) and coupled to the power source 662. The storage andcommunication unit 612 can save the sensor data in a non-volatilestorage device and pass the saved data through wireless or wiredcommunication to the sensor processor 104, patient device 106, orclinician device 108 illustrated in FIG. 1. The optional treatment unit668 may provide vibrations or pulses or release drugs that can enhancebone growth.

FIGS. 7A and 7B are top and bottom views, respectively, of oneembodiment of a sensor module 758 that can be adhered, or otherwiseplaced adjacent, to the skin of the patient. The sensor module includesa housing 760, optional adhesive pad 770, sensors 702 a, 702 b, 702 c,power source 762, communications unit 766, and sensor processor 704. Itwill be recognized that other sensor modules may have more or fewersensors and that the sensors may be the same or of different types.

The housing 760 can be made of any suitable material, such as plasticmaterials, and preferably has sufficient flexibility to fit comfortablyon the patient's skin following the anatomical contours and to also flexas the patient moves. In at least some embodiments, the housing 760 isalso water resistant to resist ingress of sweat, rain, and other fluidsinto the interior of the housing. In at least some embodiments, thehousing 760 is sufficiently water resistant to allow the patient toshower with the sensor module 758 remaining attached to the skin of thepatient and without any covering over the sensor module. In someembodiments, the housing 760 is sufficiently water resistant to allowthe patient to bathe or swim without any covering over the sensor module758.

In at least some embodiments, the housing 760 has a shape or indicia onthe housing that visually indicates or suggests the orientation of thedevice when the housing is attached to the patient. In the illustratedembodiment, one end of the device is narrower than the other end whichindicates or suggests to the user that the narrow end is pointed towardthe knee or other joint.

The illustrated embodiment also features a power light 772 that is litwhen the sensor module 758 is functioning to assure the patient that thedevice is operating. In some embodiments, the power light 772 may alsoflash or change color to indicate device functions such as, for example,a low battery, pairing with another device (for example, the patientdevice 106, clinician device 108, or network 110 of FIG. 1), activelytaking readings using one or more of the sensors (particularly forsensors that are manually or periodically activated), alert the patientthat it is time to perform exercises, change adhesives or the like.

The illustrated embodiment also features a power button 774 that can beactivated to turn the device on and, optionally, to turn the device off.In at least some embodiments, the power button 774 may also be activatedto manually direct one or more of the sensors to take readings.

The optional adhesive pad 770 is designed to hold the sensor module 758on the patient's skin. The adhesive pad 770 can have, for example, asubstrate with adhesive on both sides of the substrate so that one sidecan be adhered to the patient's skin and the other side adhered to thehousing 760. In at least some embodiments, the adhesive pad 770 can beperiodically replaced (for example, every 1, 2, 5, or 7 days or every 2,3, 4, or more weeks) as the adhesive next to the patient's skin or thehousing 760 may degrade or otherwise lose some or all of itsadhesiveness. Preferably, at least the adhesive to be adhered to thepatient's skin is selected to prevent or resist causing skin irritation.Preferably, the adhesive on both sides of the substrate is selected tobe water resistant and resist losing adherence due to contact withsweat. In at least some embodiments, the adhesive pad 770 extends aroundthe circumference of the sensor module 758, but includes one or moreopenings so allow the housing 760 to make contact with the skin of thepatient or access to the patient without an intervening portion of theadhesive pad 770.

In other embodiments, instead of the adhesive pad 770, adhesive may beapplied directly to the housing for adhering the housing with thedirectly to the skin. In yet other embodiments, instead of adhering thesensor module to the skin, the sensor module can be inserted into abrace or other item to be worn by the patient and hold the sensor modulein place at the desired position on the body. This wearable item, suchas a brace, optionally includes an opening that allows the sensor moduleto make contact with the skin of the patient.

The sensors 702 a, 702 b, 702 c, power source 762, communications unit766, and sensor processor 704 can be disposed within the housing 760. Insome embodiments, a portion of one or more of the sensors, such as atemperature, pulse, or pressure sensor; moisture sensor, strain gage,may extend through the housing to provide contact with the skin oraccess to the patient without an intervening portion of the housing 760or other parts of the sensor module 758. In some embodiments of thesensor module 758, sensor 702 a is an accelerometer, sensor 702 b is agyroscope, and sensor 702 c is a temperature sensor. The temperaturesensor can be, for example, a thermistor or an infrared sensor. Theaccelerometer 702 a and gyroscope 702 b can be used to measure range ofmotion, number of steps, type of exercise, number of exerciserepetitions or joint movements, and the like. In other embodiments, thesensors 702 a, 702 b can both be accelerometers that are optionallyin-line with each other to increase accuracy in range of motionobservations, and can be further utilized in the calculation of thepoint about which the motion is rotating. Yet other embodiments, thesensors include an accelerometer, a magnetometer, and a temperaturesensor. As will be understood, any suitable sensor described above canbe included in the sensor module and any combination of those sensorscan be used in the sensor module. It is also understood that multiplesensor modules can be utilized together to provide data refinement or toprovide comparative information, such as to show improvement in limp, ormore accurately define the positions of both sides of the joint.

Any of the power sources described above can be used for a power source762. For example, the power source 762 can be a primary cell and mayhave an expected lifetime under normal usage of at least 1, 2, or 4weeks or at least 1, 2, 3, 4, 6, 8, 10, 12, 15, 18, 24, months or more.In some embodiments, the power source 762 is rechargeable using, forexample, a recharge port in the sensor module 758 or is capable of beingwirelessly charged such as with an inductive recharge device (such as aninductive mat or sleeve), or using WiFi or ultrasonic charging asdescribed above. The power could be provided to the device by energyharvesting means, such as with cantilevered piezo reeds, a generator andpendulum setup, passive magnets rolling/sliding/bouncing through or bycoils, or the like to convert some amount of kinetic energy intoelectrical energy to be used by the device. The power source 762provides power to the sensors 702 a, 702 b, 702 c, communications unit766, sensor processor 704, and any other components in the sensormodule.

The sensor processor 704 can be any suitable processor and may include,or be coupled to, a memory unit for storing sensor data. The sensorprocessor 704 can be wired or wirelessly coupled to the sensor 702 a,702 b, 702 c for receiving data from the sensors. In some embodiments,the sensor processor 704 may include analysis algorithms for analyzingor partially analyzing the sensor data. In other embodiments, the sensorprocessor 704 may be primarily designed to receive, store, and transmitsensor data.

The communications unit 766 can be any suitable communicationsarrangement that can transmit information from the sensor processor 704or sensors 702 a, 702 b, 702 c to another device (such as the patientdevice 106, clinician device 108, or network 110 of FIG. 1.) Thecommunications unit 766 can transmit this information by any suitablewired or wireless technique including, but not limited to, Bluetooth',near field communications, WiFi, infrared, radio frequency, acoustic,optical, or using a wired connection through a data port in the sensormodule or any other communications technique presented herein or thelike.

FIGS. 8A and 8B illustrate another embodiment of a sensor module 858without (FIG. 8A) and with (FIG. 8B) an adhesive pad 870. The sensormodule 858 is similar to the sensor module 758 except in the shape ofthe adhesive pad 870 and that the housing 860 of this embodiment haspulling features 880 that facilitate gripping the sensor module 858 tomore easily remove or pull the sensor module from the skin of thepatient.

FIG. 9A illustrates another embodiments of a sensor module 958 with ahousing 960 and an adhesive pad 970. The sensor module 958 is similar tothe sensor module 758 except as described below. FIG. 9B illustrates thehousing 960 with gripping features that facilitate gripping the sensormodule 958 to more easily remove or pull the sensor module from the skinof the patient.

FIG. 9C illustrates the adhesive pad 970 with one or more shapedlocating features 982 attached to the adhesive pad and extending awayfrom a substrate 971 of the adhesive pad. FIG. 9D illustrates the bottomof the housing 960 with one or more shaped locating features 984 thatare preferably complementary in shape to the locating features 982 ofthe adhesive pad 970. The locating features 982, 984 facilitate properlyattached the adhesive pad 970 to the housing 960.

In some embodiments, a second sensor module can be used. For example,the second sensor module can be placed on the same leg on the other sideof the joint and the sensors in the two sensor module can be used tomeasure flexion angles, range of motion, and the like. The two sensormodules optionally can communicate with each other. As another example,a second sensor module may be placed on the other leg for use indetecting or observing limp or other gait deficiencies or placed on thetorso to detect or observe body orientation. A second sensor module (ormore additional sensor modules) may also be used when two or morereplacements are implanted in the body, for example, with multiple jointor vertebra replacements, to detect or observe, for example,subluxations, changes or defects in posture, scoliosis, or the like.

In at least some embodiments, each of the locating features 982, 984 hasa magnet to facilitate proper attachment and continued attachment of thehousing 960 to the adhesive pad 970. Alternatively, one set of locatingfeatures 982, 984 may have a magnet and the other set have amagnetically attractive material. In at least some of these embodiments,the adhesive pad 970 optionally has adhesive on the side of the padcontaining the locating features 982, 984.

U.S. patent application Ser. No. 15/077,793, filed on Mar. 22, 2016,incorporated herein by reference in its entirety, includes other systemsand methods of using sensors, such as a camera, for monitoring a jointor other surgical site.

As indicated above, the sensor processor or sensor communicate with apatient device or clinician device to provide sensor data or informationderived from the sensor data. FIG. 10 illustrates one embodiment of auser interface 1090 for the patient device or clinician device. Theillustrated user interface 1090 is particularly useful for a mobiledevice such as a smartphone or tablet. The user interface 1090 canprovide information such as steps per day (or number of repetitions ofan exercise or the like) and a temperature measurement as shown insection 1092. The user interface 1090 may also include a section 1092that shows graphs of the data such as the hourly number of steps, asillustrated in FIG. 10. The illustrated user interface 1090 permits theuser to select from other charts such as exercise history (labeled“ROM”), temperature, and number of impacts or shocks to the sensormodule. It will be understood that other measurement or observationsfrom the sensor described above can be graphed. In at least someembodiments, the user may also be able to select the time period of thegraph to display data in periods of time such as, for example, minutes,hours, days, or weeks.

This user interface can be useful in monitoring patient activity andprogress. The graphs in section 1094 may be useful for showing patientexercise history and progress. In some embodiments, the user interfacemay also allow the user to set goals such as, for example, a number ofsteps or a number of exercise repetitions over a particular period (forexample, 1, 2, 4, 6, or 12 hours or 1 day or 1 week). The user interfacemay also display the current status towards attaining those goals. Theuser interface may also highlight notable events, such as, for example,the largest number of steps or exercise repetitions, elevatedtemperature readings, large numbers of impacts or shocks, or the like.The user interface may also highlight the attainment of goals.

FIG. 11 illustrates a user interface 1190 that may be suitable for acomputer or web interface. The illustrated user interface includes aregion 1192 displaying the results of temperature measurements 1192 a,step measurements 1192 b, range of motion tests 1192 c, specificexercises and tests 1192 d, and adverse events 1192 e. These results mayinclude numerical information and graphical information. These resultsmay also illustrate graphically or numerically the degree of success inperforming exercises (see, for example, region 1092 d) and may alsoillustrate the degree of compliance with rehabilitation activities (suchas the number of exercise repetitions performed). Such an arrangement ofinformation can facilitate monitoring or patient progress,identification of progress or lack of progress, identification ofconcerns (such as elevated temperature or elevated number of shocks orimpacts), and the like.

FIG. 12 illustrates a user interface 1290 for a clinician to monitormultiple patients. The region 1292 includes information such as patientname, surgery date, sensor date and results of tests 1292 a, number ofadverse events, location of the orthopedic implant, and the like. Theclinician may also track number of surgeries 1294, rate of successfulrehabilitation 1296, and other suitable information.

In at least some embodiments, the user interfaces 1090, 1190, 1290 canbe web or application interfaces that are accessible when the patientdevice or clinician device accesses a server for a content provider. Inat least some embodiments, the server or other servers or memory storagedevices can store information for the web interface and may also storepatient-specific information including patient identification data,sensor data or information derived from sensor data, patient orclinician comments or the like, or any other suitable data. In at leastsome embodiments, the patient-specific information can be accessed fromthe patient device, clinician device or other device which, in someembodiments, may require providing credentials (e.g., username orpassword or both) to access the information.

The above specification, examples and data provide a description of themanufacture and use of the composition of the invention. Since manyembodiments of the invention can be made without departing from thespirit and scope of the invention, the invention also resides in theclaims hereinafter appended.

What is claimed as new and desired to be protected by Letters Patent ofthe United States is:
 1. A system for monitoring a joint of a patient,the system comprising: a plurality of sensors configured and arranged tobe disposed near a joint and configured and arranged to measure orobserve actions or physical quantities associated with the joint; and atleast one communications module coupled to the plurality of sensors andconfigured and arranged to receive data from the sensors and configuredand arranged to transmit sensor information to an external device. 2.The system of claim 1, wherein the at least one communication unitcomprises a sensor processor configured and arranged to receive thesensor data and a wireless communications unit configured and arrangedto wirelessly transmit the sensor information to or through the externaldevice.
 3. The system of claim 2, further comprising a sensor modulecomprising a housing, the plurality of sensors disposed in the housing,and the at least one communication unit disposed in the housing, whereinthe sensor module is configured and arranged to be disposed adjacentskin of the patient to monitor the joint.
 4. The system of claim 3,wherein the sensor module further comprises an adhesive pad coupleableto the housing and configured and arranged to adhesively adhere thesensor module to the skin of the patient for at least one hour.
 5. Thesystem of claim 3, further comprising a wearable article configured andarranged to receive the sensor module within the wearable article and tobe worn by the patient so that the sensor module is disposed near thejoint.
 6. The system of claim 1, wherein the plurality of sensorscomprises at least one sensor configured and arranged to provide sensordata that can be processed to determine a range of motion of the joint.7. The system of claim 6, wherein the at least one sensor comprises afirst accelerometer in combination with at least one of a secondaccelerometer, a gyroscope, or a magnetometer.
 8. The system of claim 1,wherein the plurality of sensors comprises at least two proximitysensors configured and arranged to provide sensor data that can beprocessed to determine a number of repetitions of joint movement.
 9. Thesystem of claim 1, wherein the plurality of sensors comprises at leastone temperature sensor or pulse sensor.
 10. The system of claim 1,wherein at least one of the plurality of sensors is configured andarranged to be implanted in the patient.
 11. The system of claim 1,further comprising a patient device configured and arranged to receivethe sensor information from the at least one communications module andto process the sensor information and display the processed informationfor viewing by the patient.
 12. The system of claim 1, furthercomprising a clinician device configured and arranged to receive thesensor information from the at least one communications module or from apatient device and to process the sensor information and display theprocessed information for viewing by a clinician.
 13. A sensor module,comprising: a housing configured and arranged to be disposed near ajoint of a patient and adjacent to skin of the patient; a plurality ofsensors disposed within the housing, wherein the plurality of sensorscomprises at least one sensor configured and arranged to provide sensordata that can be processed to determine a range of motion of the joint;a sensor processor disposed within the housing and coupled to theplurality of sensors and configured and arranged to receive sensor datafrom the plurality of sensors; and a communications unit disposed withinthe housing and coupled to the sensor processor and configured andarranged to transmit sensor information, based on the sensor data, to anexternal device.
 14. The sensor module of claim 13, further comprisingan adhesive pad coupleable to the housing and configured and arranged toadhesively adhere the sensor module to the skin of the patient for atleast one hour.
 15. The sensor module of claim 14, wherein the adhesivepad comprises at least one first locating feature and the housingcomprises at least one second locating feature having a shapecomplementary to a shape of the at least one first locating feature tofacilitate alignment of the adhesive pad with the housing.
 16. Thesensor module of claim 15, wherein one of the at least one firstlocating feature or the at least one second locating feature comprises amagnet and another one of the at least one locating feature or the atleast one second locating feature comprises a second magnet or amagnetically attractive material to facilitate coupling of the adhesivepad to the housing.
 17. The sensor module of claim 13, furthercomprising a wearable article configured and arranged to receive thehousing of the sensor module within the wearable article and to be wornby the patient so that the housing of the sensor module is disposed nearthe joint.
 18. The sensor module of claim 13, wherein the plurality ofsensors comprises a first accelerometer in combination with at least oneof a second accelerometer, a gyroscope, or a magnetometer.
 19. Thesensor module of claim 13, wherein the plurality of sensors comprises atleast two proximity sensors configured and arranged to provide sensordata that can be processed to determine a number of repetitions of jointmovement.
 20. The sensor module of claim 13, wherein the plurality ofsensors comprises at least one temperature sensor or pulse sensor.